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31.
The COVID-19 pandemic has the tendency to affect various organizational paradigm alterations, which civilization hasyet to fully comprehend. Personal to professional, individual to corporate, and across most industries, the spectrum of transformations is vast. Economically, the globe has never been more intertwined, and it has never been subjected to such widespread disruption. While many people have felt and acknowledged the pandemic’s short-term repercussions, the resultant paradigm alterations will certainly have long-term consequences with an unknown range and severity. This review paper aims at acknowledging various approaches for the prevention, detection, and diagnosis of the SARS-CoV-2 virus using nanomaterials as a base material. A nanostructure is a material classification based on dimensionality, in proportion to the characteristic diameter and surface area. Nanoparticles, quantum dots, nanowires (NW), carbon nanotubes (CNT), thin films, and nanocomposites are some examples of various dimensions, each acting as a single unit, in terms of transport capacities. Top-down and bottom-up techniques are used to fabricate nanomaterials. The large surface-to-volume ratio of nanomaterials allows one to create extremely sensitive charge or field sensors (electrical sensors, chemical sensors, explosives detection, optical sensors, and gas sensing applications). Nanowires have potential applications in information and communication technologies, low-energy lightning, and medical sensors. Carbon nanotubes have the best environmental stability, electrical characteristics, and surface-to-volume ratio of any nanomaterial, making them ideal for bio-sensing applications. Traditional commercially available techniques have focused on clinical manifestations, as well as molecular and serological detection equipment that can identify the SARS-CoV-2 virus. Scientists are expressing a lot of interest in developing a portable and easy-to-use COVID-19 detection tool. Several unique methodologies and approaches are being investigated as feasible advanced systems capable of meeting the demands. This review article attempts to emphasize the pandemic’s aftereffects, utilising the notion of the bullwhip phenomenon’s short-term and long-term effects, and it specifies the use of nanomaterials and nanosensors for detection, prevention, diagnosis, and therapy in connection to the SARS-CoV-2.  相似文献   
32.
OBJECTIVE: Optimal chest compression to ventilation ratio (C:V) for one-rescuer cardiopulmonary resuscitation (CPR) is not known, with current American Heart Association recommendations 3:1 for newborns, 5:1 for children, and 15:2 for adults. C:V ratios influence effectiveness of CPR, but memorizing different ratios is educationally cumbersome. We hypothesized that a 10:2 ratio might provide adequate universal application for all age arrest victims. DESIGN: Clinical study. SETTING: Tertiary care children's hospital. SUBJECTS: Thirty-five health care providers. INTERVENTIONS: Thirty-five health care providers performed 5-min epochs of one-rescuer CPR at C:V ratios of 3:1, 5:1, 10:2, and 15:2 in random order on infant, pediatric, and adult manikins. Compressions were paced at 100/min by metronome. The number of effective compressions and ventilations delivered per minute was recorded by a trained basic life support instructor. Subjective assessments of fatigue (self-report) and exertion (change in rescuer pulse rate compared with baseline) were assessed. Analysis was by repeated measures analysis of variance and paired Student's t-test. MEASUREMENTS AND MAIN RESULTS: Effective infant compressions per minute did not differ by C:V ratio, but ventilations per minute were greater at 3:1 vs. 5:1, 10:2, and 15:2 (p < .05). Effective pediatric compressions per minute were less at 3:1 vs. 5:1, 10:2, and 15:2 (p < .05) and not different between 5:1, 10:2, and 15:2 ratios. Effective pediatric ventilations per minute were greater at 3:1 than all other ratios and both 5:1 and 10:2 were >15:2 (p < .05). Effective adult compressions per minute were progressively greater with 3:1 vs. 5:1 vs. 10:2 vs. 15:2 (p < .05). Self-efficacy was assessed, and rescuers always subjectively rated 10:2 and 15:2 ratios as easier than 5:1 or 3:1 ratios for all manikins. Rescuer pulse change (exertion) was greater after pediatric and adult vs. infant CPR (p < .05), with no significant difference by C:V ratio. CONCLUSIONS: C:V ratio and manikin size have a significant influence on the number of effective compressions and ventilations delivered during ideal, metronome-paced, one-rescuer CPR. Low ratios of 3:1, 5:1, and 10:2 favor ventilation, and high ratios of 15:2 favor compression, especially in adult manikins. Rescuers subjectively preferred C:V ratios of 10:2 and 15:2 over 3:1 or 5:1. Infant CPR caused less exertion and subjective fatigue than pediatric or adult CPR technique, without significant difference by C:V ratio. We speculate that a universal 10:2 C:V ratio for one-rescuer layperson CPR is physiologically reasonable but warrants further study with particular attention to educational value and technique retention.  相似文献   
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34.
Age and sex effects on brain morphology   总被引:6,自引:0,他引:6  
1. 1. Brain morphology can be assessed readily in vivo using magnetic resonance imaging (MRI).
2. 2. In this study, the effects of age and sex on whole-brain morphology were examined using an operator-controlled computer-segmentation protocol.
3. 3. Results indicated that age was associated with gray-matter volume reduction.
4. 4. Brain-size differences between males and females were primarily attributable to whitematter volume.
5. 5. This study confirms the importance of controlling for age and sex in brain-morphology studies.
  相似文献   
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38.
PURPOSE: We have characterized the androgen receptor (AR) in a new human prostate cancer cell line, MDA PCa 2a, that has recently been established from a bone metastasis of a patient whose cancer exhibited androgen-independent growth. MATERIALS AND METHODS: Androgen responsiveness of these cells was assessed by measuring the effect of DHT and R1881 on cell growth and PSA secretion. Scatchard analysis was used to characterize the affinity and abundance of AR protein. Using a PCR based strategy, genomic DNA of the entire coding region of AR gene was sequenced to identify possible mutations. RESULTS: These cells express abundant AR (Nmax = 685 +/- 149 fmol./mg. protein), but the AR binding affinity (Kd) for DHT is only 25 nM, approximately 50-fold lower affinity than the mutated AR in LNCaP prostate cancer cells (Kd = 0.5 nM) or the wildtype AR in MCF-7 breast cancer cells (Kd = 0.4 nM). Two mutations, L701H and T877A, were identified in the ligand binding domain of the AR gene. Compared with LNCaP cells, the new cell line is significantly less responsive to DHT and R1881 as well as to other androgens such as testosterone, androstenedione, and DHEA. Similar to LNCaP cells, the ligand specificity of the AR in MDA PCa 2a cells appears to be relaxed and non-androgens such as progesterone and estradiol act as agonists although with less potency than in LNCaP cells. Interestingly, in the absence of androgens, the new cell line expresses 15-fold higher baseline levels of PSA than LNCaP. CONCLUSIONS: Two mutations were identified in the AR gene of the MDA PCa 2a cell line that are likely responsible for the decreased androgen sensitivity and altered ligand specificity observed in these cells. Thus, this new cell line with partial androgen responsiveness and PSA expression can serve as a functionally relevant model system of bone metastatic prostate cancer, and can be used to investigate the role of AR mutations in prostate cancer and its progression to androgen independence.  相似文献   
39.

Background

Central pancreatectomy is a definitive treatment for low-grade tumors of the pancreatic neck that preserves pancreatic and splenic function at the potential expense of postoperative pancreatic fistula. We analyzed outcomes after robot-assisted central pancreatectomy (RACP) to reexamine the risk–benefit profile in the era of minimally invasive surgery.

Methods

Retrospective analysis of nine RACP performed between August 2009 through June 2010 at a single institution.

Results

The average age of the cohort was 64 (range 18–75 years) with six women (67 %). Indications for surgery included: five benign cystic neoplasm and four pancreatic neuroendocrine tumor. Median operative time was 425 min (range 305–506 min) with 190 ml median blood loss (range 50–350 ml) and one conversion to open due to poor visualization. Median tumor size was 3.0 cm (range 1.9–6.0 cm); all patients achieved R0 status. Pancreaticogastrostomy was performed in seven cases and pancreaticojejunostomy in two. The median length of hospital stay was 10 days (range 7–19). Two clinically significant pancreatic fistulae occurred with one requiring percutaneous drainage. No patients exhibited worsening diabetes or exocrine insufficiency at the 30-day postoperative visit.

Conclusions

RACP can be performed with safety and oncologic outcomes equivalent to published open series. Although the rate of pancreatic fistula was high, only 22 % had clinically significant events, and none developed worsening pancreatic endocrine or exocrine dysfunction.  相似文献   
40.
Inguinal hernia surgery is one of the most common electively performed surgeries in infants. The common nature of inguinal hernia combined with the high-risk population involving a predominance of preterm infants makes this a particular area of interest for those concerned with their perioperative care. Despite a large volume of literature in the area of infant inguinal hernia surgery, there remains much debate amongst anesthetists, surgeons and neonatologists regarding the optimal perioperative management of these patients. The questions asked by clinicians include; when should the surgery occur, how should the surgery be performed (open or laparoscopic), how should the anesthesia be conducted, including regional versus general anesthesia and airway devices used, and what impact does anesthesia choice have on the developing brain? There is a paucity of evidence in the literature on the concerns, priorities or goals of the parents or caregivers but clearly their opinions do and should matter. In this article we review the current clinical surgical and anesthesia practice and evidence for infants undergoing inguinal hernia surgery to help clinicians answer these questions.  相似文献   
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